Switching regulators based on the principle of the buck cell are known, for example, from Patent WO 84/00085 or EP/O 111 493. Such switching regulators have a power switch that opens and closes according to a predetermined pattern, whereby energy is periodically fed to a choke and through the latter both to a capacitor and a load switched in parallel thereto.
The principle of the switching regulator is very simple and its construction is sturdy. The switching regulator can, however, be damaged under extreme operating conditions, especially its power switch can be damaged. Such conditions occur primarily in the event of short-circuits at the output and during turning the regulator on. In general, the conventional switching regulator reacts too slowly and is not able to handle rapid changes, that is, so-called transients.